AISI 1045 Steel (UNS G10450)


AISI 1045 is a medium carbon steel containing approximately 0.45% carbon that can be hardened by heat treatment to a maximum surface hardness of approximately Rockwell C 54-60 after flame or induction hardening.  Soft annealed medium carbon steel is intended for applications requiring moderate forming, while soft spheroidized annealed product is intended for applications requiring maximum cold forming.  1045 is used extensively by all industry sectors for applications requiring more strength and wear resistance than low carbon mild steels.

Chemical Composition

Chemical Composition (wt%) limits of AISI 1045 per ASTM A684*

Carbon 0.010 Phosphorus 0.08
Manganese 14.5-16.5 Sulfur 2.5

*Maximum, unless range is indicated

Physical Properties

Physical properties for AISI 1045 Steel

Density, lb/in3 0.284
Modulus of Elasticity, psi 29 x 106
Coefficient of Thermal Expansion, 68-212˚F, /˚F 6.39 x 10-6
Thermal Conductivity, Btu/ft hr ˚F 30.0
Specific Heat, Btu/lb ˚F 0.116
Electrical Resistivity, Microhm-in 6.42


Typical standards for AISI 1045 Steel